1. Field of the Invention
The present invention relates to an information processing apparatus, method, and program, and more particularly to modality identification for input data.
2. Description of the Related Art
It has been proposed to detect a particular object, such as a face or the like, from an image using principal component analysis (PCA) or singular value decomposition (SVD, HOSVD) as described, for example, in Japanese Unexamined Patent Publication Nos. 2006-092151 (Patent Document 1), 2009-134466 (Patent Document 2), 2005-133813 (Patent Document 3), and 2005-250863 (Patent Document 4). Patent Documents 1 and 2 describe a method of identifying an object by providing, in advance, a plurality of subspaces by a projection matrix learned through principal component analysis using sample data with respect to each object and, when an unknown image is inputted, identifying to which of the subspaces the unknown image belongs.
Patent Document 3 discloses a method for projecting an object based on principal component analysis to detect the object and estimating parameters of the object, such as the imaging direction and illumination direction of the object. Patent Document 4 describes a method in which a plurality of subspaces to be projected by a projection matrix is provided in advance using sample data representing a face at a predetermined position and sample data representing a face displaced from the predetermined position, and a determination is made as to which of a partial region cut out from a whole image or a region cut out at a position different from that of the partial region is correct.
In the conventional methods described in Patent Documents 1 to 4, an image is mapped into a feature vector space and a face or the like is detected from the distance of each class to subspace and the like in the feature vector space. Such conventional methods, however, have a problem that detection accuracy is degraded due to individual face differences or the like.
In view of the circumstances described above, it is an object of the present invention to provide an information processing apparatus and method capable of accurately and efficiently identifying a modality of input data. It is a further object of the present invention to provide a computer readable recording medium on which is recorded an information processing program for causing a computer to perform the information processing method described above.